Improvement in steam and air brakes



A. SMITH EL H. M. GDEN Steam nd Air Brakes.

No. 134,774.1;7/9] Patentedran.14,za73.

ym'y L f W3 z o y 0 u Y iff/6127523 V/f/'Zzefs es. M7 t @fda @W-f f7 i,M o( UNITED STATES ATENT. OFFICE' ALEXANDER Q. SMITH AND HENRY M. OGDEN,OF BURLINGTON, IOWA, ASSIGNORS TO THEMSELVES AND DAN. BROWN, OF SAMEPLAGE.

IMPROVEMENT IN STEAM AND AIR BRAKES.

Specification forming part of Letters Patent No. 134,774, dated January14, 1873.

.To all whom t may concern:

Be it known that we, ALEXANDER Q. SMITH and HENRY M. OGDEN, both ofBurlington, in the county of Des Moines and State of Iowa, have inventeda new and useful Improvement in Air-Brakes for Railroad Cars, of whichthe A following is a full and exact description, which will be betterunderstood by referring to the accompanying drawing making part oi' thisspecification, in which- Figure lis a vertical longitudinal section of avalve-case used by us, the interior works being represented in proiile.Fig. 2 is a plan, from beneath, of the cover of this valve-case. Fig. 3is a cross-section of that cover, showing a pipe leading to thecylinder. Fig. 4 is a section of a double valve, which is shown inproiile atG, Fig. l; and Fig. 5 is a side view of the valve D, of whicha front view is shown at D in Fig.

Our invention is an improvement upon what is known as the Westinghouseair-brake for railroad cars, the chief object being to release thecar-wheels from their gripe with sufticient promptness.

rlhe old plan is to release the brake by opening the 7scape of thethree-way cock at the engine in the pipe through which all thecompressed air is driven for the purpose of closing the brakes. In along train of ears it would take some minutes before the wheels wereentirely freed from the brakes, which would often cause delay in themovement of the train. We propose to allow each cylinder which works therespective brakes of the several ears to discharge itself with much lessdelay into the open air whenever it is desired to release the brakes.

'Io accomplish our purpose we use an airtight valve-case, A B, shaped asshown in the drawing, and provided with contrivances which we shall nowdescribe. In the bed B of this valve-case we construct cylindricalreceptacles in which the valves G and D may work freely. The stem of thevalve D is provided with wings 0r flanges g g g, which serve as guidesto this valve and leave free opportunity for the air to escape throughthe pipe F as soon as the valve D is raised from its seat. The valve Gis made with a puppet-valve, m, working within it, as shown in Fig. 4.The stem of the valve O is made cylindrical and fills its receptacle asfull as is consistent with ease of motion in rising or falling. Theinterior valve m is constructed with wings or flanges ff f, which guideit in its motions up and down. rEhe spaces thus left allow a freepassage of air as soon as this valve is raised from its seat, which isnot the ease with the valve C. We usually construct the body of thevalve-case of cast-iron, and the valves which come in frictional contactwith this iron are made of brass; but we do not coniine ourselves to theuse of anyparticular metal ineither case. The pipe E is a branch fromthe main pipe, which runs fore and aft through the train. rIhe pipe F isan escape-pipe into the open air, While the pipe E connects the interiorof the valve-case with the cylinder which works the brakes of the car towhich it is attached. Connected with the valves C and D is the lever l,working on a fulcrum at a', and having the arm which connects with thevalve O much lon ger than the other, which connects with the valve D. yWhen there is no airpressure in the valve-case A B both the valves G andm sink to their respective seats. The valve D would then be open. Butwhen the condensed air is admitted into the pipe which extendsthroughout, the train it will rush through the branch pipe E with suchforce as not only to raise the valve m from its seat, but also to carrywith it the valve C, and thus close the valve D, as shown in thedrawing. While the pressure within the valve-case continues the valve Dwill be kept closed and the valve y C will remain raised from its seat,as shown in the drawing, but the valve m will fall back into its seat assoon as the current of air ceases to iiow through the pipe E.

If a spring was attached to some portion of the lever Z oi justsufficient power to raise the long arm of that lever, and thus close thevalve D when there was no pressure in the valve-case, there would be asaving of some of the compressed air which would otherwise be, in asmall degree, wasted, but we prefer the ar rangement as shown in thedrawing.

If', when the brakes are hard on,77 the engineer wishes to release themfrom their holdV upon the wheels he will open the 7scape of thethree-way cock, which is placed in the main pipe leading throughout thetrain at or near its-connection with the reservoir of compressed air.The escape of air from the pipes will soon relieve the chief pressuretherein; and if the long arm of the lever lis twice the length of theshort arm, then, when the pressure in the pipe E becomes less .thanone-half as great as that in the valve-case A B, the valve C willdescend so as to open the valve D, and thus the cylinder, which isconnected with this valvecase, will discharge itself directly into theopen air through the pipes E and F. In order that these valves C and Dmay work with greater ease, we construct a slot oroblon g hole througheach end of the lever l, through which the pivots a a/ are inserted. Ashort link or pitman might be used for the same purpose, but we' preferthe first-named arrangement.

It is true that after the pressure in the pipe E is released in ever sogreat a degree the pressure within the valve-case upon the valves C andD will be of the same intensity, but a pound of pressure upon C willhold in equilibrium a much greater amount of pressure upon D on accountof its having a greater leverage. When, therefore, the downward pressureupon the valve G ceases to be resisted, in part, by a sufficient upwardpressure in the pipe E, a preponderance will be given to the valve C,and the valve D will be raised. The saine result would be produced bymaking the two arms of the lever Z of equal length, and then constructing the net surface of the valve C of a much greater area than that of thevalve D. We generally combine both methods.

Instead of being constructed as above represented, the valve-case may bemade in a' greater or less degree as a portion of the cylinder-head,with which it is attached.

We also contemplate the use of our improvement in any of its forms as anappendage to a steam-brake, when it would operate in substantially thesame manner as above repre- Y sented.

We make no broad claim to the use of any and every contrivance by whichall the cylinders in the Westinghouse brake may besimultaneouslydischarged into the open air in order to release the several brakes withgreat promptness; but

What we do claim as new, and desire to secure by Letters Patent, is

The valves C D, attached, respectively, to the arms of a lever, l, thesaid valves and lever being constructed and applied to operatesubstantially as and for the purpose set forth.

ALEXANDER Q. SMITH..

. HENRY M. OGDEN.

Witnesses: i

J oHN N. MAsoN, J. M. KING.

